L-carnitine therapy is effective in increasing semen quality. - GreenMedInfo Summary
Use of carnitine therapy in selected cases of male factor infertility: a double-blind crossover trial.
Fertil Steril. 2003 Feb;79(2):292-300. PMID: 12568837
Outpatient Department and Laboratory of Seminology and Reproductive Immunology at the Training Center in Andrology of the European Academy of Andrology, Rome, Italy. firstname.lastname@example.org
OBJECTIVE: To determine the efficacy of L-carnitine therapy in selected cases of male factor infertility. DESIGN: Placebo-controlled, double-blind, crossover trial. SETTING: University tertiary referral center. PATIENT(S): One hundred infertile patients (ages 20-40 years) with the following baseline sperm selection criteria: concentration, 10-20 x 10(6)/mL; total motility, 10%-30%; forward motility,<15%; atypical forms,<70%; velocity, 10-30 micro/s; linearity,<4. Eighty-six patients completed the study. INTERVENTION(S): Patients underwent L-carnitine therapy 2 g/day or placebo; the study design was 2 months of washout, 2 months of therapy/placebo, 2 months of washout, and 2 months placebo/therapy. MAIN OUTCOME MEASURE(S): Variation in sperm parameters used in the patients selection criteria, in particular, sperm motility. Excluding outliers, a statistically significant improvement in semen quality, greater than after the placebo cycle, was seen after the L-carnitine therapy for sperm concentration and total and forward sperm motility. The increase in forward sperm motility was more significant in those patients with lower initial values, i.e.,<5 x 10(6) or<2 x 10(6) of forward motile sperm/ejaculate or sperm/mL. CONCLUSION(S): Based on a controlled study of efficacy, L-carnitine therapy was effective in increasing semen quality, especially in groups with lower baseline levels. However, these results need to be confirmed by larger clinical trials and in vitro studies.